Abstract
Six new species and two new records of Crepidotus are described from Thailand. Macroscopic and microscopic descriptions with photoplates, as well as a multigene phylogeny, are provided. Crepidotus chiangraiensis sp. nov. is recognized as densely velutinous with white hairs longer near the point of attachment, not striate margin, and not hygrophanous. Crepidotus- flavocarpus sp. nov. is recognized by yellow to yellowish pileus basidiomata, margin discolorous paler yellow, densely velutinous with white hairs near the point of attachment, smooth globose basidiospores, and inverse hymenophoral trama. Crepidotus thailandicus sp. nov. is recognized by a tomentose surface with white hair when primordial to early stages and then disappearing with age when mature present long translucent-striate reward to the point of attachment becoming fade away at central. Crepidotus roseocarpus sp. nov. is recognized by large basidiomata, pileus, lamellae, and context are pastel pink, concolorous darker pink at the margin, hymenophoral trama convergent, with cylindrical terminal elements. Crepidotus-ungulatus sp. nov. is recognized by ungulate basidiomata, brownish orange near the point of attachment, the basidiomata color changed to light brown in three hours, and the margin is concolorous to the surface of the pileus. Crepidotus viscidus sp. nov. is recognized by white semicircular pileus, translucent-striate with gray to dark grey margin, lamellae pale orange to orange-white, glutinous context, smooth basidiospore and hymenophoral trama present regular form. Crepidotus lateralipes and C. striatus are reported as new records to Thailand.